I have read that the maxima ECU is adaptive in that it changes according to driving styles. I have also read that there are a few ways to reset it. Some say you can disconnect the terminal going to the positive battery post for 1/2hour. Others say it must be disconnected overnight. I also read that it can be done using the procedure below. Some say the procedure below only resets part of the ECU ut not timing and some other things. Does anybody know what must actually be done to reset the ECU?

One procedure:

How to reset ECU in 5th and 6th Generation Maxima's
1. Turn ignition switch on and wait about 3 seconds.

Repeat the following steps (2a and 2b) procedures quickly five times within 5 seconds.

2a. Fully depress the accelerator pedal (HARD).
2b. Fully release the accelerator pedal.

3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the CEL starts blinking. (here is where i think you can get a code from this.)
4. Fully release the accelerator pedal (while the CEL is still blinking)
5. Wait about 10 second.
6. Fully depress the accelerator pedal and keep it for more than 10 seconds.
7. Fully release the accelerator pedal (The CEL light will continue to blink).
8. Turn ignition switch to “OFF” position and now you can start the car. The CEL light should be gone.

Also, I have read that it takes 400-500 miles of driving for the ECU to complete readapting. If I drive heavy on the throttle during that time then what different signals does the ECU send? Does it adjust the timing, fuel, etc from that point forward?

 

for 2000 its simply disconnecting the battery, you dont need to keep it overnight, i keep it off for no more than thirty minutes. you know when its reset if you have a cd in the radio and it pops out.
for 2002+ its that process listed above.
400 miles is a little much, i believe its just a couple miles..

 

First things first - help the little guy out by running the engine at idle (if not already, warm up the engine to normal temp) for a while. The ECU can learn quite a bit from this stage since the RPMs aren't bouncing around precariously. Then go for some normal driving a few miles and let it adapt to the condition of your coil packs, plugs, O2 sensors, etc.

 

But for a 2000 or 2001 is it better to follow that porcedure or should we just simply disconnect battery?

 

I don't think that procedure works for 00-01s. Just do the battery trick.

 

Thanks for posting this - I've misplaced my Haynes and I needed to reset my ECU, but was getting the same conflicting results online.

 

I just installed an intake in my car and wanted to reset the ecu, but not sure if I'm doing it right...I followed the procedure listed above but I am unable to see the CEL light come on or blink during the procedure...any ideas???....do I even need to reset the ecu with an intake install???

 

The timing is crucial. I use my metronome for that, never failed.

 

bumping up the old thread.
you don't necessarily have to, but i did anyways.

 

Also, the engine temp is crucial too. Make sure i's warmed up.

 

I just bought a new MAF for my 2000 Maxima and I am going to install it myself, but I was told I need to take it to the dealership to get reprogrammed? Does the ECU just need to be reset? Is this something I can do myself or do I actually need to take it to the dealership?

Thanks

 

Resetting and reprogramming are two different things. Yes you have to reset the ECU. No you don't have to have the ECU reprogrammed or at least thats the general consensus. I drove around my max for two years after changing the maf without reprogramming with no problems. I had to get it done in the end for something else. Anyway, when you replace your maf you have to disconnect the battery. By the time your done, the ECU will have reset so you don't have much choice.

 

disconnect your battery for a few hours ... i had the same problem with my k&n air filter and i did the whole disconnecting battery and it picked up on the code in about 150 miles for me... i was happy when it turned off that **** was annoying

 

did it yesterday and within 10mi. of driving it came back, got codes for EGR and o2 sensor

 

mine went away after more miles then that and when i fired mine back up it came right back up like it was always there... but once it went away, never came back up..
im bout to get a custom cold air intake... that should be fun for the sensors =D

 

you dont need to reset anything...after a few days, the ECU will make any needed adjustments.

 

i got an oil change today, do i need to reset my ecu?

 

only if it was synthetic

 

so when do you reprogram (flash) and when do you reset the ECM?
how are those different?

 

reset - you set software values back to default factory settings so that the ECU can "relearn" a new mod such as an intake. (think - rolling back drivers)

reprogram (reflash) - there is a problem with the default software values. Nissan will have new software that needs to be loaded to correct the problem. (think - installing new drivers)

 

I see.
So in my case that I changed the TB, ECM and maybe I add the MAF should I do a nice reflash of ECM. I got the ECM from junkyard and not sure how old that is.

Also is there any way we can do the reflash ourselves or anyone beside dealer (stealer)?

 

An ECM replacement requires the dealer and the NATS security system program to reprogram all your keys. Might as well check for any required updates (reflashes) at the same time.

 

The reseting we did ourselves I am trying to figure out if it is worth it to do the reflash. since my car is still idleing on 1700rpm

 

Just to know ... Did somebody know the services number of the ECM for maxima 2001 20th aniversary. I need to buy one on ebay but i want to be sure is the good one
thank you

 

Easiest way is to make sure the engine is a full operating temperture. Turn off, disconnect the negative terminal from the battery. Step on the brake pedal, hold it down and then turn on the headlights about 10 seconds. That will clear out any remaining charge in the system.

I haven't noticed much difference in my car resetting the ECU but I noticed a huge difference when I had my 626 since the previous owner drove it so conservatively.

 

For a 2000 it's the negative terminal correct?

 

Please confirm - it is not clear - does the procedure displayed below reset also 5th generation Maxima (2001)?
I don't have an OBD scanner, but I know now the system does not show up any codes, can this good situation change after reset?

WHere is the CEL lamp that should blink in Maxima 2001?

 

Did you mean displayed above, because i see no procedure below.

And if you are referring to the one this thread is about the answer is no.

 

Thanks!, if I reset the ECU this will clear the error codes ?

 

Yes.

 

Bringing this back up, this should work for my 2000 I30t correct?

 

No, follow the 00-01 procedure. This method is for 3.5s only.

 

Sorry to bump this thread. My 2003 maxima threw a cel code p0128 yesterday on my way t work.i have tried to search but didnt really come up on anything. My question is ,could it still be the thermostat if my car is not heating up???

Also checked coolant and it is fine. Was trying to reset ecu using this procedure but its not working for me.tia

 

Might be the ECT.

http://www.nicoclub.com/FSM/maxima/2003/ec.pdf


Page 225

 

If you have the P0128 and the car is not getting warm, it is almost definitely the thermostat. It's a quick change. Buy the housing from your Nissan dealer. I believe it cost about 20 bucks.

 

What i ment to say is its not getting above normal operating temp.i reset the ecu and the cel hasnt came back, granted ive only drove it more den 5miles.also the fans are turning on once it gets to normal temp as usual. And now that i think of it coolant was a little low and i topped it off .should i keep driving it to see if the code comes back?

 

How do you know it's not getting to normal opaerting temp?

Those are short distances and if you're in a fairly chilly climate, you wont reach operating temp.

Takes my car a good while to get there.

Also, the fans don't run on when you reach operating temp, they turn on (1 or both, high or low) when certain conditions have been met, and one of those conditions is not operating temp.


Operating temp is also a fairly loose term.

 

Okay car doesnt overheat.fans turn on which means thermostat is opening up right??also if it was the ect sensor wouldnt the fans not turn on??i might be wrong ,just trying to see if anyone else has gone thru this problem before?..
Im going to drive the car to work today to see if the cel comes back on .

 

No, the fans turn on as a failsafe if the ECT is wacked.

 

Will resetting the ecu erase my timing advance??? Tgat would suk